Compositions and methods for detecting mycobacterium tuberculosis

Abstract

The present invention relates to the field of Mycobacterium tuberculosis. More specifically, the present invention provides compositions and methods for detecting M. tuberculosis. In a specific embodiment, a method comprises the steps of (a) contacting a patient sample with a solid support coated with antibodies to carbapenem resistance factor A (CrfA); washing unbound molecules from the solid support using a buffer; and incubating the solid support with a beta-lactamase substrate. In certain embodiments, the beta-lactamase substrate is chromogenic. In another embodiment, the method further comprises the step of visually detecting a color change from the hydrolysis of the substrate by CrfA protein bound to the antibodies on the solid support. In yet another embodiment, the method further comprises the step of measuring color intensity of the strip at 490 nm using a spectrophotometer.

1 . A kit comprising:
 a. a solid support coated with antibodies to carbapenem resistance factor A (CrfA); and   b. a beta-lactamase substrate.   
     
     
         2 . The kit of  claim 1 , further comprising instructions for using the kit to detect CrfA in a sample obtained from a patient. 
     
     
         3 . The kit of  claim 1 , wherein the solid support is selected from the group consisting of a strip, a disk or a multi-well plate. 
     
     
         4 . The kit of  claim 1 , wherein the solid support is a strip. 
     
     
         5 . The kit of  claim 1 , further comprising a buffer for washing unbound protein following a contacting step between a patient sample and the solid support. 
     
     
         6 . The kit of  claim 1 , wherein the beta-lactamase substrate is chromogenic. 
     
     
         7 . The kit of  claim 6 , wherein the chromogenic beta-lactamase substrate is nitrocefin. 
     
     
         8 . A method comprising the steps of:
 a. contacting a patient sample with a solid support coated with antibodies to CrfA;   b. washing unbound molecules from the solid support using a buffer; and   c. incubating the solid support with a beta-lactamase substrate.   
     
     
         9 . The method of  claim 8 , further comprising the step of visually detecting a color change from the hydrolysis of the substrate by CrfA protein bound to the antibodies on the solid support. 
     
     
         10 . The method of  claim 8 , further comprising the step of measuring color intensity of the strip at 490 nm using a spectrophotometer. 
     
     
         11 . The method of  claim 8 , wherein the patient sample is selected from the group consisting of blood, serum, plasma and urine. 
     
     
         12 . The method of  claim 8 , wherein the solid support is selected from the group consisting of a strip, a disk or a multi-well plate. 
     
     
         13 . The method of  claim 8 , wherein the solid support is a strip. 
     
     
         14 . The method of  claim 8 , wherein the beta-lactamase substrate is chromogenic. 
     
     
         15 . The method of  claim 14 , wherein the chromogenic beta-lactamase substrate is nitrocefin.